Kepler-452b

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PHIon
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Kepler-452b

Post by PHIon » Tue Jul 28, 2015 11:17 am

I have tried to apply daniel's method of scaling down exoplanets to moons (as demonstrated in his paper "The Colonization of Tiamat") to Kepler-452b. Here is some of the data we've been given:

http://iopscience.iop.org/1538-3881/150/2/56/article

The orbital period of Kepler-452b is supposed to be around 385 days. I looked around for moons in our solar system with a similar period and found Nereid, which has an irregular orbit around Neptune of about 360 days:

http://nineplanets.org/data.html

If you haven't read "The Colonization of Tiamat," here is daniel's method of scaling what are reported to be exoplanets going around stars down to what may actaully be moons:
11.The extreme orbital speeds of exoplanets become scaled down to moons orbiting Jupiter-like planets at the normal speeds observed in our own solar system.

As an example to item #11, we can take a conventional star with known exoplanets, such as Kepler-101, a single sun with two planets, 101-b and 101-c. 101-b orbits this star in 3.49 days, and 101-c in just 6.03 days. The fastest planet we have in our solar system is Mercury, taking 88 days. That’s a big difference. But what if we scale the star Kepler-101 down to a Jupiter-size planet? Jupiter has a bunch of moons and if it is a Jupiter-size planet, 101-b and 101-c should show similar orbital properties as some of Jupiter’s moons.
Jupiter is roughly 1/10th the size of the sun, so we can just adjust the orbital distance by a factor of 10:
101-b: 0.045 AU / 10 = 0.0045 AU.101-c: 0.0648 AU / 10 = 0.00648 AU.
So, we are looking for a couple of moons at these distances, with similar orbital periods (the period is not scaled as it is time, not spatial distance):
101-b: 0.0045 AU, 3.49 days.101-c: 0.00648 AU, 6.03 days.
Lo and behold…
Europa: 0.0045 AU, 3.55 days. Almost an exact match to Kepler 101-b.Ganymede: 0.00716 AU, 7.15 days. Just a little further out than Kepler 101-c.

To paraphrase Obi-Wan Kenobi, “that’s no planet, it’s a moon!”
"just down the road a little way, turn left, cross the drawbridge, and you will be my guest tonight."
-- directions to the grail castle

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